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★★★ Open House ★★★
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CTR September 2018
Mingle With the Masters; All About Plastics; Alan Kay's Amazing New Computer (in 1972)
“Clearly, it can be nearly impossible to know whether an ad or a post on Facebook is legitimate or a ploy by a foreign government to turn you against other Americans. You can look for language clues, or investigate the posts that pop up on your feed, or try to get familiar with posts by known Russian pages. But unless a page is taken down, you probably won’t know for sure.”  The following is the customized paragraph from an interactive article in today’s New York times, offering a quiz that every upper elementary student should take. At

Dear CTR Subscribers,
As a reminder of how far Moore’s Law has taken our hardware, it’s fun to take a look under the hood of Alan Kay’s “A Personal Computer for Children for All Ages” written August 1972. Here’s how he describes the storage on his device. “The only technology that currently exists which can handle the modest, though important, demand for a writable file storage is magnetic oxide on plastic in the form of tape cassette or floppy disk. Until recently, tape handling typically required a conglomeration of pinch rollers,
capstans, solenoids and motors. Now the problems of constant tape tension and differential drive have been solved by a number of companies, the most elegant being the cassette by 3M which uses a ‘magic’ driveband which contacts the outside of the tape takeup reels and requires only one motor for read, write, search and rewind. Four tracks of tape at a bit density of 1600 bpi allows 6400 bits/inch to be stored and retrieved. Our requirement thus demands 1250 inches (or 105 feet) of tape in the cassette. Of course there will be gaps, etc., so to play safe, our fantasy cassette will have 50% more tape or 150 feet.”

Apps to Connect Your Child to Artistic Genius
We’re really excited about a new CTREX feature we have that lets us tag specific apps to match a topic. Following the theme of our cover app for this issue (Mixerpiece), we pulled up 14 similar titles.

The news that LEGO is thinking about using plant-based plastic raised our curiosity about this amazing substance. See page 3, or visit